Mask washer



April 15, 1969 R. B. WAY

MASK WASHER Filed an 10, 1967 Sheet of 2 RoQEAT 8-. WA)! R. B. WAY

MASK WASHER April 15, 1969 Sheet Filed July 10, 1967 INVENTOR Kaaem' 5. WAY

United States Patent 3,438,355 MASK WASHER Robert B. Way, 439 Vermont Ave., Erie, Pa. 16505 Filed July 10, 1967, Ser. No. 652,109 Int. Cl. B05b 1/28, 15/04 US. Cl. 118301 Claims ABSTRACT OF THE DISCLOSURE tion in a tank of paint solvent. An agitator is provided in the tank and a means to heat the solvent. A lateral track is supported below the masks when in the painting position to remove paint from the masks.

This invention relates to coating machines, and more particularly, to the type of coating machine used for applying paint to articles of manufacture through masks, stencils, or the like.

In painting or otherwise coating articles of manufacture through masks, it is always a diflicult problem to remove the surplus paint from the mask. The invention discloses herein an improved machine for cleaning masks.

It is, accordingly, an object of the present invention to provide an improved mask cleaning machine.

Another object of the invention is to provide a machine for cleaning masks which is simple in construction, economical to manufacture, and simple and efiicient to use.

Still another object of the invention is to provide an improved combination painting machine and mask washing machine.

With the above and other objects in view, the present invention consists of the combination and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawings and more particularly pointed out in the appended claims, it being understood that changes may be made in the form, size, proportions, and minor details of construction without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawings:

FIG. 1 is an isometric view of a machine according to the invention; and

FIG. 2 is a schematic side view of the machine.

Now with more particular reference to the drawings, the machine shown has a frame 10 which supports paint guns 33 and mask support frames 11.

The several mask support frame 11 best shown in FIG. 2 are carried by the index chain 12 which is, in turn, supported on sprockets 23-, 24, 25, 26, 27, 28, 29, 30, 31 and 32. These sprockets are driven intermittently by the air motor and gear reducer arrangement 18 in synchronism with the painting operation as will later appear. Cross shaft connects the driving mechanism for the sprockets on both sides of the machine.

The paint guns 33 are moved by the gear reducer 21 and air motor 34, which reciprocate the paint guns from side to side of the machine below the mask. Paint is supplied to the gun through paint hoses 14 which are coiled around the rod 35 that is in position in front of the machine at a particular time. Air for operating the air motor 34 is supplied through hose 19 which is likewise coiled around the rod 35.

3,438,355 Patented Apr. 15, 1969 When a mask is in the painting position, in the position indicated at the left of FIG. 2, articles to be painted may be supported on the mask and clamped into position by means of the air cylinders 16 in a manner familiar to those skilled in the art, for example, as shown in Patent 2,725,085 issued to Robert B. Way et al. The cylinders 16 will be operated by air from a suitable source of compressed air.

After the article supported on the mask indicated has been painted or after several articles have been painted so that the mask requires cleaning, the mask that has been used at position A is indexed to the position support B inside the cleaning tank 13 where the mask washing or cleaning operation takes place. The mask support 11 remains in tank 13 until mask support 11 is ready to be cleaned. The index chain then continues to rotate to bring the mask through the position indicated at 11" where it is dried while mask support 11 is in the cleaning tank during the next cycle, the dried mask 11" is moved into the position of the mask indicated at 11 where it can be used in the next cycle.

A suitable paint solvent will be placed in the tank 13 to clean the paint from the masks. The tank may be filled to the desired level so that the masks are completely submerged and a suitable agitation means such as shown, for example, in Patent 3,320,963 to Walker may be used of a type familiar to those skilled in the art to apply solvent to the masks.

The machine is provided with a control panel indicated at 20 which has a suitable control box, switches, and other control equipment for controlling the indexing of the masks attached to supports 11, 11 and 11", the oscillation of the guns 33, and clamping the articles by means of the air cylinders 16.

In operation masks which have a. side that is an intaglio of the articles to be painted are attached to mask support 11, 11' and 1.1". When the machine is started, one support will be disposed at 11, one at 11 and one at 11". An article to be painted will be forced. into engagement with the mask on the support 11 by the air cylinders 16. The paint guns will traverse from side to side below the article spraying paint through the openings in the masks out at the work. When it is necessary to clean the mask, as soon as the paint gun stops, the operator actuates the control connected to air motor 18. The chain 12 will be driven until the mask support 11 with the mask attached moves to the position of support 11 in the tank 13 of solvent. The mask in the solvent will be moved to the position of support 11 where it will dry while the mask that was in the position of support 11" will move to the position of support .11 where it will receive another article to be painted.

The part to be painted is loaded manually into mask at 11. Operator actuates the controlsspray guns on reciprocating carriage paint over and backoperator unloads part. Sequence is repeated until paint build up on mask necessitates washing.

Operator actuates manual valve to start air motor drive which indexes chain carrying masks. Mask 11 is moved into washing tank, mask 11' is moved to drying position, mask 11" is moved into painting position. The operator can then resume painting operation.

When the mask is lowered into the washing tank its bottom edge is captured by the V 40* of the mask rocker 41. As the rocker moves back and forth on the platform 53 which is supported on the tank bottom and driven by the slotted arm and eccentric at 12, and crank arm 51, the mask which is pivoted at its chain attachment, at 43, is swung back and forth in the mask washing solution.

(The solution of a low boiling point F.) and nonflammability. Other non-flammable chlorinated hydrocarbons would probably work but the high boilers such 3 as tri-chlor would require such a high operating temperature (around 160-180 F.) that the paint would be baked on the mask. Acetone would probably work but its flammability makes the operation quite hazardous.)

The mask 11' is rocked continuously while the operator paints with the new clean mask 11. (It has been discovered that the mask is usually clean in about 2 minutes. The operator will usually paint in one mask for about 3 minutes.) When the mask in the painting station needs cleaning the operator again actuates the mask index valve repeating the mask washing cycle.

The solvent is boiled by the hot water heating pipes 45 on the bottom of the mask washing tank. The heat of the solution, the bubbling of the solution by boiling and the rocking of the mask 11 all contribute to the cleaning action. The mask becomes heated by being immersed in the hot solution so that when it is raised from the solution at the next index the liquid on the mask is quickly evaporated. An extraction speed of 11 ft./ min. is used until the mask is clear of the tank. Then a valve cammed by the timing chain shifts to a high speed index (30 to 40 ft./min.).

The finned condensing coils 48 at the top of the tank are cooled by a F. refrigerant producing a temperature differential of approximately 100 between the coils and the vapor. This causes the vapors to condense on the coils creating a low vapor pressure barrier which prevents the escape of the vapors from the tank. The refrigerating system is equipped with a defrost cycle using hot gas through the tubes to remove the ice accumulation on the coils. The coil condensate is caught in troughs under the coils and piped to a separator box which separates the water from the solvent returning the solvent to the tank and diverting the water to a drain.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In combination, a painting machine and a mask cleaner,

said machine having a frame,

mask support means on said frame,

coating dispensing means on said frame,

masks supported on said mask support means,

means on said machine for supporting articles to be coated above said masks and above said coating dispensing means,

said mask support means comprising two spaced indexing chains,

said mask support means comprising two mask support members,

said mask support members each extending from one said indexing chain to the other, and attached thereto,

a cleaning position for cleaning said masks,

means to index said chains whereby said masks are moved from said position between said coating means and said mask support means to said cleaning position,

and mask cleaning means at said cleaning position to clean said paint from said masks.

2. The combination recited in claim 1 wherein said mask cleaning means comprises a tank containing paint solvent,

and means to move said mask support means through a path defined by a generally vertical plane into said tank.

3. The combination recited in claim 2 wherein heating tubes are disposed in said tank to boil said solvent.

4. The combination recited in claim 3 wherein, refrigerated tubes are supported on said tank abOVe said solvent and adjacent the path through which said mask moves, whereby solvent evaporated by said heating tubes is condensed on said mask at its moves past said tubes.

5. The combination recited in claim 2 wherein,

means is provided on said tank to move said mask in said solution to agitate said mask.

6. The combination recited in claim 1 wherein each said mask support means comprises a relatively wide, flat plate like member,

one end of each said plate like member being attached to each said chain,

means to support said plate like member in a generally horizontal plane wherein said mask support is in position between said articles and said coating means,

7. The painting machine recited in claim 1 wherein said tank has a relaitvely deep elongated, narrow mask receiving member therein for said mask to move into for cleaning.

8. The painting machine recited in claim 7 wherein means is provided to move said chains each of which move about a continuous track from said coating position up and toward said tank,

then up and toward said tank,

then toward said tank and over said tank,

then down into said tank,

then up out of said tank,

then toward said painting position, then to said painting position. 9. The combination recited in claim 1 wherein, said means to move said mask comprises a V-shaped member open at its top and disposed in said solvent, one said mask being disposed in said V-shaped memher, and means to oscillate said V-shaped member with said mask therein to cause said solvent to move over the surface thereof. 10. The combination recited in claim 9 wherein said means to oscillate said V-shaped member comprises a motor and eccentric member.

References Cited UNITED STATES PATENTS 2,280,811 4/1942 Edhofer et al. 134-75 2,795,206 6/1957 Faber 1l870 X 3,036,582 5/1962 Lisciani l34160 X 3,320,963 5/1967 Walker 134l60 X WALTER A. SCHEEL, Primary Examiner. J. P. MCINTOSH, Assistant Examiner.

U.S. Cl. X.R. l34-75 

